RESUMO
The production possibility of 161Tb and 155Tb by irradiating of natural dysprosium with gamma rays obtained by decelerating an electron beam with an energy of 55 MeV has been demonstrated experimentally. The yield of 161Tb was 14.4 × 103 Bq × µA-1 × h-1 × cm2 × gDy2O3-1. Simultaneously, upon irradiation, 155Dy is formed with the yield of 25 × 103 Bq × µA-1 × h-1 × cm2 × gDy2O3-1, which leads to the formation of 1.6 × 103 Bq × µA-1 × h-1 × cm2 × gDy2O3-1 of 155Tb. It has been shown that the isolation of terbium radioisotopes from tens of mg of dysprosium target can be achieved by extraction chromatography, and final separation yield was 39%. The impurity of 160Tb is 7.3% of the 161Tb activity at EOB.
Assuntos
Disprósio , Radioisótopos , Disprósio/química , Térbio/químicaRESUMO
Ni46Mn41In13 (close to 2-1-1 system) Heusler alloy was studied by magnetization measurement dependence on the temperature in magnetic fields of up to 13.5 T. The magnetocaloric effect measured by the direct method in quasi-adiabatic conditions showed a maximum value of ∆Tad = -4.2 K at a temperature T = 212 K in a magnetic field of 10 T in the region of martensitic transformation. The structure of the alloy was studied by transmission electron microscopy (TEM) as a function of the temperature and the thickness of the sample foil. In the temperature range from 353 to 215 K, at least two processes were established. The results of the study indicate that the concentration stratification occurs according to the mechanism of spinodal decomposition (conditionally spinodal decomposition) into nanoscale regions. At a temperature of 215 K and lower, martensitic phase with 14 M modulation is observed in the alloy at thicknesses greater than 50 nm. Some austenite is also observed. In foils with thickness of less than 50 nm in a temperature range from 353 to 100 Km only the initial austenite, which has not transformed, was found.
Assuntos
Biota , Dípteros/classificação , Sedimentos Geológicos , Lagos , Modelos Biológicos , Animais , Clima , Dípteros/fisiologiaRESUMO
OBJECTIVES: To report a premarket multicenter trial to test the feasibility of a transvaginal silicone-coated polyester synthetic mesh sling in women with anatomic incontinence. METHODS: Fifty-one patients in four centers underwent transvaginal placement of a silicone-coated polyester synthetic mesh sling (American Medical Systems) during an 8-month period. Of the 51 patients, 31 were part of a prospective institutional review board-approved feasibility trial in three centers funded by American Medical Systems (group 1) and 20 underwent implantation by a single surgeon and their data were retrospectively reviewed (group 2). The studies were done concomitantly, and all slings were fixed transvaginally with bone anchors. All patients in group 1 were followed up at 4 weeks, 6 months, and 1 year (as applicable) with repeat questionnaires, physical examinations, and pad tests. RESULTS: In group 1, 20 patients completed 6 months of follow-up. Ten patients (32%) required a second surgical procedure at an average of 183 days (range 68 to 343) postoperatively. Eight patients (26%) had vaginal extrusion of the mesh, one (3%) required sling lysis, and one (3%) required sling removal because of infection. In group 2, 8 patients (40%) underwent sling removal for vaginal extrusion at a mean of 160 days (range 83 to 214). CONCLUSIONS: Transvaginally placed silicone-coated mesh slings used for the treatment of urinary incontinence demonstrated an unacceptably high vaginal extrusion rate in this study. Once identified, this study was immediately terminated, and this product was not marketed for this application in the United States.
Assuntos
Poliésteres , Próteses e Implantes/efeitos adversos , Telas Cirúrgicas/efeitos adversos , Incontinência Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Procedimentos Cirúrgicos Urológicos/métodosRESUMO
The propensity of patients with carcinoma in situ (CIS) of the bladder to progress to invasive and metastatic disease is clearly established. Today, the standard therapy in treating patients with CIS of the bladder is intravesical bacillus Calmette-Guerin (BCG). Nevertheless, patients who fail intravesical BCG have few viable options except to undergo a radical cystectomy. Valrubicin (N-trifluoroacetyladriamycin-14-valerate) is a new semisynthetic derivative of the anthracycline antibiotic doxorubicin that has been shown to benefit patients with BCG-refractory CIS of the bladder. Intravesical instillation of valrubicin is well-tolerated, safe and can be durable. Early non-randomised studies show promise and the current utilisation of this drug is limited to patients with BCG-refractory CIS of the bladder who are not good surgical candidates. Randomised studies of intravesical valrubicin for the treatment of superficial bladder cancer are ongoing.
Assuntos
Antineoplásicos/uso terapêutico , Carcinoma in Situ/tratamento farmacológico , Carcinoma de Células de Transição/tratamento farmacológico , Doxorrubicina/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Administração Intravesical , Ensaios Clínicos como Assunto , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Guias como Assunto , Humanos , Estrutura MolecularRESUMO
OBJECTIVES: To compare how urinary symptoms affect the quality of life in groups of men with postprostatectomy incontinence treated with collagen versus artificial urinary sphincter implantation. METHODS: Two cohorts of men, one which received urethral collagen injection and one artificial urinary sphincter (AUS) implantation, were surveyed with a validated quality-of-life questionnaire to assess how their urinary dysfunction impacted their daily activities. The mean impact score and bother score for the two groups were compared. In addition, the overall degree of continence between the groups was assessed. RESULTS: At a mean follow-up of 19 months, 8 (20%) of 41 patients treated with collagen injections were at least socially continent, requiring one pad daily or less. In comparison, 27 (75%) of 36 men treated with an AUS were at least socially continent (P <0.001). Both the impact score and the bother score from the quality-of-life questionnaire were significantly lower in the group treated with the AUS than in the group treated with collagen. CONCLUSIONS: Patients receiving an AUS achieved significantly higher continence rates. Also, the quality of life of men treated with an AUS was improved compared with that of the men treated with collagen injection.